The computer controlled ES–1 provides separate isolated reed relays to signal rain and snow. The rain relay operates during precipitation at temperatures above 32°F (0°C) and the snow relay operates during precipitation at temperatures below 38°F (3.3°C). The ES–1 considers both rain and snow as likely during precipitation at temperatures between 32°F (0°C) and 38°F (3.3°C). The overlap is critical to the control of snow melting systems during the spring and fall when accumulations occur at temperatures above freezing.

The relay contacts provide a simple means for connecting the ES–1 to building automation computers and PLCs in both commercial and residential applications. The NEC Class 2 U-L Listed outlet power supply included can provide the 12 to 15 volt 5 watt d.c. required by the ES–1.

The ES–1 uses customer supplied 1/2" conduit as a mounting means. The interface is placed outdoors at a location exposed to snow and rain but protected from vandalism.